Known in the art is a method of controlling valves of a compression reactor of a free-piston type (cf. U.S. Pat. No. 2,814,551, published Nov. 26, 1957, Cl. 23-1). As disclosed in this patent, the method of controlling valves of a compression reactor is performed by alternately opening and closing the compression reactor inlet valves, which normally open into the reactor.
The inlet valves are opened and closed by electromagnets each time the piston occupies a predetermined position.
However, when this prior art method is employed, great difficulties arise in starting up the compression reactor as in the process of starting, as well as changing the modes of operation, the valves should open and close with the piston occupying the positions which differ from those occupied by the piston during the steady opertion of the reactor.
Besides, as experiments showed, this prior art method of controlling valves of a compression reactor fails to ensure the stable operation of the reactor with the gas pressure fluctuating at the inlet and outlet of the reactor.
Such fluctuations, within certain limits, generally occur in practice during the operation of a compression reactor in any chemical production line.
Known in the art is a device for controlling a compression reactor (cf. U.S. Pat. No. 2,814,551, published Nov. 26, 1957, Cl. 23-1), comprising drives actuating inlet valves of the compression reactor and made in the form of an electromagnet rigidly connected with the inlet valves.
The electromagnets of the drives actuating the inlet valves are connected to drive control units designed to produce control signals for energizing the electromagnets. The drive control units include a mechanical device rigidly coupled with a piston and determining its coordinate. This prior art device for controlling valves of a compression reactor carries out control over a steady operation of the reactor by way of supplying gas into each working space of the reactor when the piston is in the predetermined positions and ceasing the gas supply with the piston occupying another position.
This is ensured due to the opening and closing of the inlet valves which open into the working space under the action of the electromagnets energized in response to a signal supplied by the respective drive control unit.
The drive control unit produces said signal at the instant its mechanical device for determining the piston coordinate registers the predetermined position of the piston freely reciprocating inside the reactor and separating two working spaces from each other.
However, this device interferes with the sealing of the reactor working spaces as the piston is mechanically associated with the drive control units arranged outside the reactor. The absence of a reliable sealing is especially harmful in the case the compression reactor handles hypertoxic and gaseous mixtures, as well as gaseous mixtures self-igniting in the air.
In addition, the heretofore described device opens and closes the reactor inlet valves depending only on the piston position and irrespective of the actual pressures existing in the working spaces and supply lines, at which it is indeed necessary to start or cease the gas supply into the working spaces from the supply lines. To ensure the stable operation of the compression reactor, the inlet valves should be opened and closed depending on the relation between the pressures in the working spaces and in the respective supply lines.